The film market demands polypropylene resins that can produce a special combination of film properties. Typically high clarity, high gloss polypropylene films can be produced by cast, double bubble (tubular), and water quenched blown film processes. Excellent optical film properties can also be obtained through biaxial orientation (BOPP) by the tender-frame process. An air-cooled blown film process, which is widely used to produce polyethylene film, does not produce high clarity films using conventional polypropylene resins.
Achieving high clarity, high gloss blown films made from polypropylene using existing processing technology is desirable. Producing a blown film with a high modulus is also desirable.